Here is an update to the ConeUnwrap script, which works on circular cones with axis perpendicular to the base.
It uses two buttons to select cone with apex vs conical frustum. (Using Michaels method in History command.)
Also the frustum unwrap line segments were redone, so the Unwrap is Sweep ready. (Do NOT use planar, as UV isocurve would likely not match.)
The script appears to work just fine under MoI4Dec2017beta.
- Brian

I typed up some documentation which might be nice in a wiki...
A couple of remarks: Holes in the cone, or bites out of the cone, or curves on the cone, can be unwrapped using Flow, with the cone face and unwrap Sweep face.
Also, in the event the holes disrupt the base circle, slantseam, or top circle, substitutes can be created by the user, or use a substitute intact cone or frustum.


Edit 1/1/2018, Corrected 2 "bugs" in the script. New version is here: (post 33)
http://moi3d.com/forum/index.php?webtag=MOI&msg=6175.33